The developer and formulator of surfactants for granular detergents must consider a wide variety of possibilities with limited (sometimes inconsistent) information, and then strive to provide overall improvements in one or more of a whole array of criteria, including performance in the presence of free calcium in complex mixtures of surfactants and polymers, e.g. cationic polymers, trends to low wash temperatures, formulation changes, enzymes , various changes in consumer habits and practices, and the need for biodegradability.
Further, granular compositions should employ materials that enhance the dissolution, or rate of product mixing, with water. Further, granular detergents should employ materials that enhance the tolerance of the system to hardness, especially to avoid the precipitation of the calcium salts of anionic surfactants. Precipitation of the calcium salts of anionic surfactants is known to cause unsightly deposits on fabrics, especially dark fabrics. In addition, precipitation of surfactants can lead to losses in performance as a result of the lower level of available cleaning agent. In the context provided by these preliminary remarks, the development of improved surfactants for use in granular laundry detergents is clearly a complex challenge. The present invention relates to improvements in such surfactant compositions.
It is an aspect of the present invention to provide mixtures of the mid-chain branched primary alkyl surfactants which are formulatable with other surfactants to provide cleaning compositions having one or more advantages, including increased resistance to water hardness, greater efficacy in surfactant systems, improved removal of greasy or particulate body soils, and the like.